Orders Summary

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Order Summary for Pleuronectiformes
Main Ref.:	Nelson, J.S., 1994
Order:	Pleuronectiformes flatfishes
Class:	Actinopterygii (ray-finned fishes)
Sister Order:	Tetraodontiformes 15 M years
Ref.:	Carroll, R., 1988 Helfman, G., B. Collette and D. Facey, 1997
First fossil record:	late Tertiary middle Miocene
Occurs in:	Marine Freshwater Brackish
Remarks:	Adults not bilaterally symmetrical, with one eye migrating to the other side of the cranium; dorsal and anal fins with long bases, dorsal fin base overlapping at least the neurocranium except in Psettodes; body highly compressed, somewhat rounded on eyed side and flat on blind side; eyes can protrude above body surface allowing fish to see when buried in the substrate; usually six or seven branchiostegal rays, rarely eight; body cavity small; adults almost always without swim bladder; scales cycloid, ctenoid, or tuberculate. About four species probably occur in freshwater, while another 20 species that are normally marine occasionally enter freshwater.
Class etymology:	Greek aktis = ray, thunderbolt, beam + Greek pterygion, diminutive of pteryx = wing, fin. Ref. 45335.
Order etymology:	Greek, pleura = similar, ribe, side + Greek, nektos = to swim + Latin, forma = shape. 1849. Ref. 45335.
Families:	11 Achiridae , Achiropsettidae , Bothidae , Citharidae , Cynoglossidae , Paralichthyidae , Pleuronectidae , Psettodidae , Samaridae , Scophthalmidae , Soleidae

*Ref.:*
	( e.g. 9948)

Page created by: Eli, 17.10.00, last modified by Eli, 15.02.05.